Change .help-block tag for "Forms => Default styles" example into <span>

docs/base-css.html

@@ -835,7 +835,7 @@ For example, <code>section</code> should be wrapped as inline.
             <legend>Legend</legend>
             <label>Label name</label>
             <input type="text" placeholder="Type something…">
-            <p class="help-block">Example block-level help text here.</p>
+            <span class="help-block">Example block-level help text here.</span>
             <label class="checkbox">
               <input type="checkbox"> Check me out
             </label>

docs/templates/pages/base-css.mustache

@@ -772,7 +772,7 @@
             <legend>Legend</legend>
             <label>{{_i}}Label name{{/i}}</label>
             <input type="text" placeholder="{{_i}}Type something…{{/i}}">
-            <p class="help-block">{{_i}}Example block-level help text here.{{/i}}</p>
+            <span class="help-block">{{_i}}Example block-level help text here.{{/i}}</span>
             <label class="checkbox">
               <input type="checkbox"> {{_i}}Check me out{{/i}}
             </label>